ok, i have windows xp, and the newest version of itunes. i have several videos on my ipod and today i converted them to put on my ipod using right click and "convert selection for iPod" once converted i popped in my ipod-30gig video-and updated the new videos onto my ipod. i found my new videos on my ipod's menu and the videos play fine, but there is no sound. these same videos do have sound when i play them on my computer in my itunes library. what do i do???